Indeed, pedophilia is a mental disorder recognized in modern medicine. However, unlike other mental illnesses, it will be exempt from liability in certain case. Pedophilia is considered a serious crime in most countries around the world because pedophiles are fully aware of their actions and commit the crime intentionally. Therefore, although medicine recognizes pedophilia as a mental disorder, but the law still deals with this issue strictly.
Is there any part of the world that it isn't a major crime. No country will ever have a soft spot for pedophiles except the one passing the law is actually in the same line of disorder, even families won't cover any member if one of them is pedophile, it's an offense that can't be overlooked, some areas or communities will serve such offender first punishment if caught in the act, before being picked up by the police.
So bad that people would commit offenses, without double thinking if the reverse was the case, what will be their response to someone doing the same to their children, when it gets to a level of pedophile, there is no crime at extreme such a person won't commit.